Multiple pump



Oct, 13, 1953 w. SANBORN 2,655,110

MULTIPLE PUMP Filed Jan. 11, 1951 3 Sheets-Sheet l IN V EN TOR.

Oct. 13, 1953 w. SANBORN 2,655,110

MULTIPLE PUMP Filed Jan. 11, 1951 3 Sheets-Sheet 2 INVEN TOR.

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Oct. 13,- 1953 w. L. SANBORN 2,655,110

MULTIPLE PUMP Filed Jan. 11, 1951 3 Sheets-Sheet 5 Patented Oct. 13, 1953 UNITED STATES PATENT OFFICE MULTIPLE PUMP William L. Sanborn, Whitefish Bay, Wis.

Application January 11, 1951, Serial No. 205,498

12 Claims. l

This invention relates to a multiple pump, one of which preferably acts upon a liquid medium, and the other upon a gaseous medium. It is particularlyuseful in theoilburner field wherein the fluid medium is the fuel being consumed and the .gaesous'medium .is the primary at for atomizing and supporting combustion.

Simplicity of construction, low power requirements for operation of the pump, easy maintenance,and elimination of troublesome mechanical seals (whichterm, as used throughout this specification, is intended to include stuffing boxes as well.) are among the :more important objects of the invention. These and others, however, will bemore apparent as the disclosure proceeds and the following description is read :in conjunction withythe accompanying drawings in which Fig. 1 is a vertical cross-sectional view showing a preferred embodiment of .the pump, the section being taken on the line -l-,l of Fig. 2;

' Fig. 2- is an end elevational view taken from the right with reference to Fig. 1 with parts broken away to expose particularly the intake valve arrangement;

Fig. 3 is a transverse sectional view taken on the line 3- -3 of Fig. l and showing particularly the air rotor construction;

Fig. 4 is a view taken on the line 4-4 of Fig. 1 and showing particularly the air intake and discharge ports;-

. Fig. 5- is a perspective view showingone of the air rotor blades or pumping elements;

Fig. 6 -a tnansverse sectional view taken on he line eoi Fi i:

1 Fig. '7: is. a transverse sectional view through the oil pump; the section being- ;taken on the,- line h of Fig. l;

Fig. 8 is an enlarged ,iragmentary sectional viewshamingv the check valve in the exhaust line for the oil pump; and

Fig. 9 is a perspective view showing, the oil pump piston.

The invention may obviously be variously modifled Within the scope of the appendedclaimsand the present disclosure of av preferred form of the invention is merely for the purpose of complying with section 4888 of the revised statutes.

General organization erally designated B in side-by-side relationship thereto, the rotor elements 10 and H, respective-- ly, of which constitute integral portions of a shaftl2 which is suitably mounted within a two-part pump housing generally designated C. The air intake for the pump A is through an adjustably tensioned check valve generally designated l3, and the air exhaust port is indicated generally at M (Fig.4).

The oil intake and discharge ports are indicated at l5 and H5 in Fig. '7.

It is important to be able to adjust independently the oil and air pumps, and to this-end, the volumetric delivery of the oil pump B may conveniently be altered by suitable adjustment of an adjusting device generally designated IT, and the adjustable intake valve l3 provides the necessary means for controlling .theaction of the air pump A. For reasons that will later appear, the

I use of an. adjustable .air intake valve is particularly advantageous in a dual pump of the type herein described.

One characteristic feature of the present invention is the absence of .the usual mechanical seals which because of their inefficiency consume a considerableamount of power.

uisite primary air for supporting combustion on a H. P. motor utilizing. not more than 130 watts in effecting this .delivery. The conven-.

tional oil and .air pumps .now commercially available require almost double the power under such conditions, and the reason for thisis because a worn mechanical seal of the rotary type takes from 22 to 40 Watts each in merely overcoming the friction of the seal, whereas a stufiing box or packed seal absorbs even more .power.

The air pump The air pump A is a rotary pump which has a circular pump chamber recess H3 in the pump housing Ill. The rotor In is also circular in form, but is eccentrically mounted within the recess 1-3 as bestshown in Fig. 3 with. the point of tangencybeing indicated at 20. The rotor H] is slotted. as indicated at 2| to receive pumping elements or vanes 22 which are preferably of the form shown in Fig. 5, and-are made of hard,

wear-resistant material such as Bakelite or the like. The vanes are slotted as indicated at 23 so air can not be trapped within the bottom of the slots 2| to thereby impose an unnecessary load upon the pump motor, and also to provide positive pressure behind the vanes to augment centrifugal force in holding the vanes in contact with the cylinder wall.

On the face of the mating pump housing or casing 24 are provided arcuate intake and discharge passages 25 and 26, respectively, it being noted that the ports are on opposite sides of the point of tangency 20 and considerably overlap the face of the juxtaposed rotor III. The purpose of this overlap is so that the face 21 of the rotor I9 is subjected to the discharge pressure of the pump in order that the pump shall be forced to the left in Fig. 1 against the face 28 of the pump chamber recess I8, this face serving as a sealing surface.

It will be seen that as the shaft I2 is rotated in a counter-clockwise direction when viewed as in Fig. 3, the vanes 22 are thrown outwardly by centrifugal force and air pressure behind the vanes against the cylindrical surface of the pump chamber I8 and draw air from the intake passageway 25 due to the expanding crescent-shaped pump chamber as the rotor revolves, and the air is then compressed as the pump chamber space begins to decrease (which will occur opposite the point of tangency 29) with the compressed air being expelled through the discharge passageway 26 into a series of communications leading to the discharge port I4.

The face 28 of the pump chamber I8 (see Fig. 1) is ground smooth to form a sealing surface, and in order that this face of the rotor may be kept at relatively low pressure, the rotor I is pierced by a passageway 29 that connects the left face or lower pressure side of the rotor with the right face or higher pressure side of the rotor. Since the discharge port 26 considerably overlaps the face of the rotor II), the discharge pressure exerts a force or axial thrust against the rotor I0, and continually maintains it in firm sealing engagement with the face 28 of the housing I9. In this way, normal running clearance may be provided on the right hand side of the rotor I 0 (Fig. 1), and when the pump is assembled, the pump will maintain its effective seal at the surface 28 regardless of wear on the rotor.

It will be noted that the air rotor In is supported in somewhat cantilever fashion from the oil pump rotor II with which it is integral, the oil pump rotor constituting a large bearing surface for support of the oil pump rotor II, the air pump rotor I0 and the shaft I2. The shaft I2 projects loosely through an opening 30 in the casing 24 and merely serves to transmit torque from the driving motor to the air and oil pump rotors. The shaft extends through an air intake chamber 3| and has good running clearance with a cover plate 32 which closes the air intake chamber 3|. Preferably the end of the shaft I2 is flattened on one side or provided with a square head as indicated at 33 for ready attachment to a motor (not shown).

Since the oil pump rotor constitutes the sole bearing support for the air and oil pump rotors, it is unnecessary to provide accurately aligned bearings. as is usual. Furthermore, the axial thrust of the air pressure causing the air rotor II] to be maintained in sealing engagement with the surface 28 serves to maintain the shaft '4 I2 in its proper running position and takes away any undesirable eccentric loading on the oil pump bearing.

In order that oil which may creep along the shaft I2 into the chamber 3| will not pass outwardly through the cover plate 32, the shaft is preferably equipped with an oil spinner 34 which intercepts and centrifugally discharges any oil that may be traveling outwardly along the shaft I2 to the air intake chamber 3|, where it passes through a bronze filter material 35 to one of the air intake passages 36. The bronze filter material acts also as a silencer in cutting down noise caused by air passing through the air pump.

Air intake regulation Air delivered from the air intake chamber 3| to the interior of the air pump chamber recess I8, and all air and oil that may pass through the passageway 29 of the rotor III must pass through the air intake regulator l3. By referring to Figs. 1 and 2, it will be seen that air that enters the passageway 36 from the intake chamber 3| is moved outwardly of the casing 24 through a passage 31 which communicates with the air intake passageway 25 through a side opening 38. Seated within the passageway 37, however, is a spring-pressed check valve 39 which rests upon a seat 40 and is urged to seated position by a spring 4|. The tension on the spring 4| may be varied by suitable adjustment of an adjusting screw 42 which may be locked in place by a lock nut 43. Preferably a protective cap 44 is threadedly mounted over the end of the adjusting screw 42 to discourage unauthorized manipulation of the adjusting screw 42.

Obviously, by increasing the force with which the spring 4| is urged against the check valve 39, the head pressure of the air pump is reduced, and conversely, by decreasing such pressure, the regulated head pressure is increased.

Since the passage 29 in the rotor I9 is closely adjacent to the oil pump B, some oil may pass between the running clearance of the oil pump rotor II and the bore 45 in the housing I9 that receives the rotor I with the result that this oil will tend to travel along the shaft I2 to the air chamber 3| where it is deposited on the floor of the chamber 3| by the oil spinner 34, and is then picked up by the air intake 36 where it is transmitted to the air intake passageway 25 through the check valve 39. It will be noted that when a slug of oil passes through the passageway 31 and check valve 39, the valve 39 may readily yield to accommodate the oil slug, and then immediately reseats itself for subsequent control of the air intake and air discharge pressure. In this way effective regulation of intake and discharge pressures are obtained regardless of oil content of incoming air.

It should also be noted that oil, in passing from the oil pump B to the passageway 29, must go through the running clearances of the oil pump (i. e., between the rotor and the bore 45), and since this clearance is very small, the oil is effectively strained.

The shaft I2 immediately adjacent to the rotor I0 is preferably slightly undercut or grooved as indicated at 46 to provide an annular chamber to receive oil through the passageway 29, where it is held for ready distribution along the surface of the shaft by a felt washer 41 which is mounted in a suitable groove in the casing 24.

The two halves of the pump housing C, that is.

diums may be used as well as air, and the specification and claims should be construed accordingly.

I claim:

1. In a combination oil and air pump, a housing having a circular air pump chamber therein one side face of which constitutes a sealing surface, and the opposed side face thereof having a discharge port, a rotor mounted in the air pump chamber, pumping elements associated with the rotor adapted to produce a pumping action in the pump chamber when the rotor is rotated, means for rotating the rotor, said discharge port overlapping the adjacent side of said rotor, whereby the rotor is urged into sealing engagement with said sealing surface, said housing also having an oil pump chamber adjoining the air pump chamber adjacent said sealing surface, an oil pump rotor in the oil pump chamber mounted rigidly with and rotating with the air pump rotor, and means for relieving pressure along said sealing surface.

2. In a combination oil and air pump, a housing having a circular air pump chamber therein one side face of which constitutes a sealing surface, and the opposed side face thereof having a discharge port, a rotor mounted in the air pump chamber, pumping elements associated with the rotor adapted to produce a pumping action in the pump chamber when the rotor is rotated, means for rotating the rotor, said discharge port overlapping the adjacent side of said rotor, whereby the rotor is urged into sealing engagement with said sealing surface, said housing also having an oil pump chamber adjoining the air pump chamber adjacent said sealing surface, an oil pump rotor in the oil pump chamber mounted rigidly with and rotating with the air pump rotor, and means for relieving pressure along said sealing surface, said pressure-relieving means including a passage way through the rotor.

3. In a multiple pump, a pump housing having an oil pump chamber and an air pump chamher in side-by-side relationship, a shaft rotatably supported in the housing and having an oil pump rotor and an air pump rotor rigidly mounted thereon for rotation within said oil and said ail pump chambers, respectively, pumping elements carried by said rotors, intake and discharge passages leading to the oil and air pump chambers; respectively, said passages including an air discharge port in the pump housing communicating with the discharge side of the air pump chamber and substantially overlapping the side of the air pump rotor that is remote from the oil pump, whereby said air pump rotor is urged by the discharge pressure of the air pump into sealing engagement with the opposed face of the air pump chamber, and means for relieving pressure along said opposed face of the air pump chamber, said pressure-relieving means including a passageway through the air pump rotor.

4. In a multiple pump, a pump housing having an oil pump chamber and an air pump chamber in side-by-side relationship, a shaft rotatably supported in the housing and having an oil pump rotor and an air pump rotor rigidly mounted thereon for rotation within said oil and said air pump chambers, respectively, pumping elements carried by said rotors, intake and discharge passages leading to the oil and air pump chambers, respectively, said passages including an air discharge port in the pump housing communicating with the discharge side of the air pump chamber and substantially overlapping the side of the air pump rotor that is remote from the oil pump, whereby said air pump rotor is urged by the discharge pressure of the air pump into sealing engagement with the opposed face of the air pump chamber, said oil pump rotor having an extended bearing in said pump housing and constituting the main bearing support for the shaft and said rotors, and means for relieving pressure along said opposed face of the air pump chamber, including a passageway communicating with the oil pump chamber, extending through said air pump rotor, and communicating with said intake passage for the air pump.

5. In a multiple pump, a pump housing having an oil pump chamber and an air pump chamber in side-by-side relationship, a shaft rotatably supported in the housing and having an oil pump rotor and an air pump rotor rigidly mounted thereon for rotation within said oil and said air pump chambers, respectively, pumping elements carried by said rotors, intake and discharge passages leading to the oil and air pump chambers, respectively, said passages including an air discharge port in the pump housing communicating with the discharge side of the air pump chamber and substantially over-' lapping the side of the air pump rotor that is remote from the oil pump, whereby said air pump rotor is urged by the discharge pressure of the air pump into sealing engagement with the opposed face of the air pump chamber, means in-- cluding a passageway for delivering oil that has leaked into the space between the oil pump rotor and the air pump rotor to said intake passage for the air pump, and an adjustable check valve in said intake passage for the air pump located intermediate the air pump chamber and the passageway that communicates with said space between said air pump rotor and said oil pump rotor, said adjustable check valve including resilient means urging said check valve to seated position, said resilient means being yieldable to permit oil to pass through said check valve, and means to vary the force with which said resilient means urges said check valve to seated position to control the discharge pressure of said air pump.

6. In a multiple pump, a pump housing having an oil pump chamber and an air pump chamber in side-by-side relationship, a shaft rotatably supported in the housing and having an oil pump rotor and an air pump rotor rigidly mounted thereon for rotation within said oil and said air pump chambers, respectively, pumping elements carried by said rotors, intake and discharge passages leading to the oil and air pump chambers, respectively, said passages including an air discharge port in the pump housing communicating with the discharge side of the air pump chamber and substantially overlapping the side of the air pump rotor that is remote from the oil pump, whereby said air pump rotor is urged by the discharge pressure of the air pump into sealing engagement with the opposed face of the air pump chamber, said oil pump rotor having an extended bearing in said pump housing constituting the main bearing support for said shaft and rotors, and means for relieving pressure on said opposed face of the air pump chamber including a passageway through said air pump rotor, and an adjustable check valve in the intake passage for said air pump, whereby the discharge pressure of the air pump may be controlled.

7. In a multiple pump, a pump housing having an oil pump chamber and an air pump chamber in side-by-side relationship, a shaft rotatably supported in the housing and having an oil pump rotor and an air pump rotor rigidly mounted thereon for rotation within said oil and said air pump chambers, respectively, pumping elements carried by said rotors, intake and discharge passages leading to the oil and air pump chambers, respectively, said passages including an air discharge port in the pump housing communicating with the discharge side of the air pump chamber and substantially overlapping the side of the air pump rotor that is remote from the oil pump, whereby said air pump rotor is urged by the dis charge pressure of the air pump into sealing engagement with the opposed face of the air pump chamber, an adjustable check valve in the intake passage for said air pump whereby the discharge pressure of the air pump may be controlled, means for separately adjusting the volu-metric discharge of said oil pump, and means for relieving pressure along said opposed face of the air pump chamber, said pressure-relieving means including a passageway extending from said opposed face to the intake passage for the air pump.

8. In a multiple pump, a pump housing having an oil pump chamber and an air pump chamber in side-by-side relationship, a shaft rotatably supported in the housing and having an oil pump rotor and an air pump rotor rigidly mounted thereon for rotation within said oil and said air pump chambers, respectively, pumping elements carried by said rotors, intake and discharge passages leading to the oil and air pump chambers, respectively, said passages including an air discharge port in the pump housing communicating with the discharge side of the air pump chamber and substantially overlapping the side of the air pump rotor that is remote from the oil pump, whereby said air pump rotor is urged by the discharge pressure of the air pump into sealing engagement with the opposed face of the air pump chamber, said oil pump rotor having an extended bearing in said pump housing and constituting the main bearing support for the shaft and said rotors.

9. In a multiple pump, a pump housing having an oil pump chamber and an air pump chamber in side-by-side relationship, a shaft rotatably supported in the housing and having an oil pump rotor and an air pump rotor rigidly mounted thereon for rotation within said oil and said air pump chambers, respectively, pumping elements carried by said rotors, intake and discharge passages leading to the oil and air pump chambers, respectively, said passages including an air discharge port in the pump housing communicating with the discharge side of the air pump chamber and substantially overlapping the side of the air pump rotor that is remote from the oil pump, whereby said air pump rotor is urged by the discharge pressure of the air pump into sealing engagement with the opposed face of the air pump chamber, said oil pump rotor having an extended bearing in said pump housing and constituting the main bearing support for the shaft and said rotors, said urging of the air pump rotor into sealing engagement with said opposed face of the air pump chamber aiding in main" taining the alignment of the shaft with respect to said extended bearing.

10. In a combination oil and air pump, a pump housing having a cylindrical oil pump chamber and an adjacent air pump chamber eccentrically positioned with reference thereto, said air pump chamber being of greater diameter than the oil pump chamber and having a planar, sealing, side face adjacent to the oil pump chamber and a pressure side face remote therefrom provided with a discharge port, said housing also having intake and discharge passageways for the oil pump chamber, an intake port for the air pump chamber, and intake and discharge passageways communicating with the intake and discharge ports associated with the air pump chamber, a rotary shaft mounted in the housing having an oil pump rotor portion occupying the oil pump chamber and constituting both a rotor for the oil pump and a main cantilever bearing support for the shaft, an air Dump rotor portion occupying the air pump chamber, overlapping said air discharge port and having a planar side face adapted to be urged into sealing engagement with said sealing side face of the air pump chamber by the air pump discharge pressure in said air discharge port, and a stub shaft portion projecting loosely through said pressure side face of the air pump chamber, and piston and vane elements in said oil and air pump rotors respectively.

11. A combination oil and air pump as set forth in claim 10 in which means are provided for relieving pressure adjacent to said sealing side face of said air pump chamber.

12. A combination oil and air pump as set forth in claim 10 in which said oil pump includes a piston slidable within a transverse bore in said oil pump rotor portion, an adjustable positioning pin rotatably engaging said piston, the stroke of said piston being determined by the eccentric p0- sitioning of said pin with relation to the axis of rotation of said oil pump rotor portion.

WILLIAM L. SANBORN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,671,399 Brady May 29, 1928 1,756,707 Sundstrand Apr. 29, 1930 1,980,404 Harman Nov. 13, 1934 2,018,692 Waite Oct. 29, 1935 2,070,662 Johnson Feb. 16, 1937 2,225,803 Smith Dec. 24, 1940 2,255,785 Kendrick Sept. 16, 1941 2,318,337 Schlosser May 4, 1943 2,333,323 Livermore Nov. 2, 1943 2,371,081 Tucker Mar. 6, 1945 2,409,477 De Lancey 1- Oct. 15, 1946 2,411,602 Tweedale Nov. 26, 1946 2,549,714 Shannon Apr. 17, 1951 

